Blame app/src/App.tsx at main - concept-collection/hitandrun-interactive

concept-collection / hitandrun-interactive

9fbdc3e Interactive hit-and-run sampling of a 2D convex regionJeremy Magland 1 month ago1import { useEffect, useState, type CSSProperties } from "react";

2import {

3 RegionView,

4 type Points,

5 type Segment,

6 type Pt,

7} from "./render/RegionView.js";

8import { onData, onHostEvent, sendToMATLAB } from "./bridge.js";

10/** Payload from the numbl script: a convex region (CCW polygon) plus the

11 * hit-and-run samples drawn from it. Mirrors what hitandrun_sampler.m sends,

12 * both as the initial `Data` and as the `data` event after "New region". */

13interface HitAndRunData {

14 type: "hitandrun";

15 region: Points;

16 samples: Points;

17 n: number;

d9d003f Add non-convex (star) regions with a general hit-and-run samplerJeremy Magland 1 month ago18 convex?: boolean; // false → non-convex (star) region

9fbdc3e Interactive hit-and-run sampling of a 2D convex regionJeremy Magland 1 month ago19}

21function isHitAndRunData(d: unknown): d is HitAndRunData {

22 return (

23 !!d &&

24 typeof d === "object" &&

25 (d as HitAndRunData).type === "hitandrun" &&

26 !!(d as HitAndRunData).region &&

27 !!(d as HitAndRunData).samples

28 );

29}

31/** `samples` event payload: fresh points for the *same* region (after Resample

32 * or moving the samples slider). */

33interface SamplesEvent {

34 x: number[];

35 y: number[];

36 n: number;

37}

d9d003f Add non-convex (star) regions with a general hit-and-run samplerJeremy Magland 1 month ago39// Discrete sample-count choices; the slider indexes into the active array.

9fbdc3e Interactive hit-and-run sampling of a 2D convex regionJeremy Magland 1 month ago40const SAMPLE_CHOICES = [10, 100, 1000, 10000, 100000, 1000000];

d9d003f Add non-convex (star) regions with a general hit-and-run samplerJeremy Magland 1 month ago41// Non-convex sampling runs in the interpreter (no JIT), so cap it lower.

42const SAMPLE_CHOICES_NONCONVEX = [10, 100, 1000, 10000];

9fbdc3e Interactive hit-and-run sampling of a 2D convex regionJeremy Magland 1 month ago43const DEFAULT_N = 10000;

45// Sampling movie: reveal points one at a time. Each frame shows the chord the

46// step samples along AND the point that landed on it, together.

47const MOVIE_STEP_MS = 750;

48const MOVIE_LAST_INDEX = 41; // animate sampling of points up to this index

50interface MovieState {

51 step: number; // index of the point currently being sampled

52}

d9d003f Add non-convex (star) regions with a general hit-and-run samplerJeremy Magland 1 month ago54/** The in-region segment(s) hit-and-run samples along: the line through

55 * (px,py) with direction (dx,dy), intersected with the polygon. One segment

a50c671 Non-convex: add local-segment vs. union sampling modeJeremy Magland 1 month ago56 * for a convex region, possibly several for a non-convex one. With `localOnly`

57 * it keeps just the segment containing the current point (t = 0) — matching the

58 * sampler's local-segment mode. Mirrors the sampler's geometry, so it

59 * reproduces each step exactly. */

d9d003f Add non-convex (star) regions with a general hit-and-run samplerJeremy Magland 1 month ago60function regionSegments(

9fbdc3e Interactive hit-and-run sampling of a 2D convex regionJeremy Magland 1 month ago61 region: Points,

62 px: number,

63 py: number,

64 dx: number,

a50c671 Non-convex: add local-segment vs. union sampling modeJeremy Magland 1 month ago65 dy: number,

66 localOnly: boolean

d9d003f Add non-convex (star) regions with a general hit-and-run samplerJeremy Magland 1 month ago67): Segment[] {

68 if (Math.hypot(dx, dy) < 1e-12) return [];

9fbdc3e Interactive hit-and-run sampling of a 2D convex regionJeremy Magland 1 month ago69 const m = region.x.length;

d9d003f Add non-convex (star) regions with a general hit-and-run samplerJeremy Magland 1 month ago70 const ts: number[] = [];

9fbdc3e Interactive hit-and-run sampling of a 2D convex regionJeremy Magland 1 month ago71 for (let i = 0; i < m; i++) {

72 const j = (i + 1) % m;

73 const ex = region.x[j] - region.x[i];

74 const ey = region.y[j] - region.y[i];

d9d003f Add non-convex (star) regions with a general hit-and-run samplerJeremy Magland 1 month ago75 const denom = dy * ex - dx * ey;

76 if (Math.abs(denom) < 1e-12) continue;

77 const wx = region.x[i] - px;

78 const wy = region.y[i] - py;

79 const s = (dx * wy - dy * wx) / denom; // position along the edge

80 if (s >= 0 && s < 1) ts.push((wy * ex - wx * ey) / denom);

9fbdc3e Interactive hit-and-run sampling of a 2D convex regionJeremy Magland 1 month ago81 }

d9d003f Add non-convex (star) regions with a general hit-and-run samplerJeremy Magland 1 month ago82 ts.sort((a, b) => a - b);

83 const segs: Segment[] = [];

84 for (let k = 0; k < ts.length - 1; k++) {

85 const tm = (ts[k] + ts[k + 1]) / 2;

a50c671 Non-convex: add local-segment vs. union sampling modeJeremy Magland 1 month ago86 if (!pointInPolygon(region, px + tm * dx, py + tm * dy)) continue;

87 // Local mode: keep only the in-region interval straddling t = 0.

88 if (localOnly && !(ts[k] <= 0 && ts[k + 1] >= 0)) continue;

89 segs.push({

90 x0: px + ts[k] * dx,

91 y0: py + ts[k] * dy,

92 x1: px + ts[k + 1] * dx,

93 y1: py + ts[k + 1] * dy,

94 });

d9d003f Add non-convex (star) regions with a general hit-and-run samplerJeremy Magland 1 month ago95 }

96 return segs;

97}

99function pointInPolygon(region: Points, x: number, y: number): boolean {

100 const n = region.x.length;

101 let inside = false;

102 for (let i = 0, j = n - 1; i < n; j = i++) {

103 const xi = region.x[i];

104 const yi = region.y[i];

105 const xj = region.x[j];

106 const yj = region.y[j];

107 if (yi > y !== yj > y && x < ((xj - xi) * (y - yi)) / (yj - yi) + xi) {

108 inside = !inside;

109 }

110 }

111 return inside;

9fbdc3e Interactive hit-and-run sampling of a 2D convex regionJeremy Magland 1 month ago112}

113

114const prefixPoints = (p: Points, k: number): Points => ({

115 x: p.x.slice(0, k),

116 y: p.y.slice(0, k),

117});

118

119export function App() {

120 const [data, setData] = useState<HitAndRunData | null>(null);

121 const [n, setN] = useState(DEFAULT_N);

122 const [busy, setBusy] = useState(false);

123 const [movie, setMovie] = useState<MovieState | null>(null);

a50c671 Non-convex: add local-segment vs. union sampling modeJeremy Magland 1 month ago124 // Non-convex sampling mode: false = sample the union of all in-region

125 // segments the line makes; true = only the segment through the current point.

126 const [local, setLocal] = useState(false);

9fbdc3e Interactive hit-and-run sampling of a 2D convex regionJeremy Magland 1 month ago127

128 useEffect(() => {

129 // Initial region + samples (script → page via `Data`).

130 const offData = onData(d => {

131 if (isHitAndRunData(d)) {

132 setData(d);

133 setN(d.n);

134 setMovie(null);

135 }

136 });

137 // "New region": the script sends a full fresh payload.

138 const offFull = onHostEvent("data", d => {

139 if (isHitAndRunData(d)) {

140 setData(d);

141 setN(d.n);

142 setBusy(false);

143 setMovie(null);

144 }

145 });

146 // Resample (same region): only the points change.

147 const offSamples = onHostEvent("samples", ev => {

148 const s = ev as SamplesEvent;

149 if (!s || !Array.isArray(s.x)) return;

150 setData(prev =>

151 prev ? { ...prev, samples: { x: s.x, y: s.y }, n: s.n } : prev

152 );

153 setBusy(false);

154 setMovie(null);

155 });

156 return () => {

157 offData();

158 offFull();

159 offSamples();

160 };

161 }, []);

162

163 // Movie clock: advance phase/step on a timer (a setTimeout chain — the effect

164 // reruns whenever `movie` changes). Ends (→ full cloud) past the last index.

165 useEffect(() => {

166 if (!movie || !data) return;

167 const lastIndex = Math.min(data.samples.x.length - 1, MOVIE_LAST_INDEX);

168 const id = setTimeout(() => {

169 setMovie(m => {

170 if (!m) return m;

171 const next = m.step + 1;

172 return next > lastIndex ? null : { step: next };

173 });

174 }, MOVIE_STEP_MS);

175 return () => clearTimeout(id);

176 }, [movie, data]);

177

d9d003f Add non-convex (star) regions with a general hit-and-run samplerJeremy Magland 1 month ago178 const nonConvex = !!data && data.convex === false;

179 const choices = nonConvex ? SAMPLE_CHOICES_NONCONVEX : SAMPLE_CHOICES;

a50c671 Non-convex: add local-segment vs. union sampling modeJeremy Magland 1 month ago180 // `local` only applies to non-convex regions.

181 const useLocal = nonConvex && local;

d9d003f Add non-convex (star) regions with a general hit-and-run samplerJeremy Magland 1 month ago182

a50c671 Non-convex: add local-segment vs. union sampling modeJeremy Magland 1 month ago183 // Re-draw `count` samples in the current region (script round-trip). The

184 // sampling mode (`localMode`) can be overridden — the local checkbox passes

185 // its new value directly, since the `local` state hasn't committed yet.

186 const resample = (count: number, localMode: boolean = local) => {

9fbdc3e Interactive hit-and-run sampling of a 2D convex regionJeremy Magland 1 month ago187 if (!data) return;

188 setBusy(true);

d9d003f Add non-convex (star) regions with a general hit-and-run samplerJeremy Magland 1 month ago189 sendToMATLAB("resample", {

190 n: count,

191 x: data.region.x,

192 y: data.region.y,

193 convex: data.convex !== false,

a50c671 Non-convex: add local-segment vs. union sampling modeJeremy Magland 1 month ago194 local: localMode,

d9d003f Add non-convex (star) regions with a general hit-and-run samplerJeremy Magland 1 month ago195 });

9fbdc3e Interactive hit-and-run sampling of a 2D convex regionJeremy Magland 1 month ago196 };

197

d9d003f Add non-convex (star) regions with a general hit-and-run samplerJeremy Magland 1 month ago198 // Generate a brand new region (convex or not) and sample it.

199 const newRegion = (count: number, convex: boolean) => {

9fbdc3e Interactive hit-and-run sampling of a 2D convex regionJeremy Magland 1 month ago200 setBusy(true);

a50c671 Non-convex: add local-segment vs. union sampling modeJeremy Magland 1 month ago201 sendToMATLAB("newRegion", { n: count, convex, local });

d9d003f Add non-convex (star) regions with a general hit-and-run samplerJeremy Magland 1 month ago202 };

203

204 // Checkbox: switch region type. Clamp N to the active set's max first.

205 const setNonConvex = (makeNonConvex: boolean) => {

206 const c = makeNonConvex ? SAMPLE_CHOICES_NONCONVEX : SAMPLE_CHOICES;

207 const clamped = Math.min(n, c[c.length - 1]);

208 setN(clamped);

209 newRegion(clamped, !makeNonConvex);

9fbdc3e Interactive hit-and-run sampling of a 2D convex regionJeremy Magland 1 month ago210 };

211

a50c671 Non-convex: add local-segment vs. union sampling modeJeremy Magland 1 month ago212 // Checkbox: switch the non-convex sampling mode; resample the same region.

213 const setLocalMode = (value: boolean) => {

214 setLocal(value);

215 resample(n, value);

216 };

217

9fbdc3e Interactive hit-and-run sampling of a 2D convex regionJeremy Magland 1 month ago218 const toggleMovie = () => {

219 if (movie) {

220 setMovie(null);

221 } else if (data && data.samples.x.length >= 3) {

222 setMovie({ step: 2 });

223 }

224 };